Apartments/Condos, homes, warehouses, technically if one is going to consider gears wheels then windows that open/close are doors too. There are a host more examples, but it all depends on how one chooses to define the existence of either.
Apartments/Condos, homes, warehouses, technically if one is going to consider gears wheels then windows that open/close are doors too. There are a host more examples, but it all depends on how one chooses to define the existence of either.